How to do backdoor Roth IRA conversion for TY 2021 in 2022?

There is a helpful article for Roth IRA conversion.  I would like to know if the steps laid out there still are applicable if I made a nondeductible contribution and then conversion to Roth IRA soon after in 2022 (before 4/18/22), but for TY2021.

 

Thanks.

 

Kwei